Development of the F-35 has been marked by delays and cost
increases. The Pentagon’s $395.7 billion estimate for the total
cost of development and production of 2,443 fighters is a 70
percent increase since the initial contract with Bethesda,
Maryland-based Lockheed Martin Corp. (LMT) was signed in 2001.

The incident involved a propulsion fueldraulic line. The
fueldraulic system saves weight by using jet fuel instead of the
customary hydraulic fluid to lubricate mechanical parts.

Detached Line

“An initial inspection discovered a detached fueldraulic
line in the aft portion of the engine compartment,” Matthew
Bates, a spokesman for Pratt and Whitney Military Aircraft, said
in an e-mailed statement.

“A team of Pratt & Whitney and Rolls-Royce engineers is
investigating the cause,” Bates said. London-based Rolls-Royce
Holdings Plc (RR/) makes the components of the propulsion system that
enable the aircraft to perform short takeoff and vertical
landing operations.

DellaVedova said, “it is the first time we’ve experienced
an event with the propulsion fueldraulic line.” The affected
component isn’t used on the Navy or Air Force versions of the
F-35, he said.